230 research outputs found
Charles F. Scott
Professor Charles F. Scott, recipient of the American Institute of Electrical Engineers Edison medal
Is NIPPV Superior to CPAP in Maintaining Targeted Oxygen Saturation Ranges in Preterm Infants on Moderate Non-Invasive Respiratory Support?
Background: Non-invasive positive pressure ventilation (NIPPV) and continuous positive airway pressure (CPAP) are non-invasive respiratory supports commonly used in preterm infants. There is conflicting data on the superiority between these two modes of non-invasive respiratory support. The objective of this study was to determine if oxygen saturation is more within the target range on NIPPV compared to CPAP using the data from histograms.
Methods: Retrospective analysis of premature neonates (\u3c 1500 grams, gestational age \u3c 30 weeks) admitted to the NICU for which oxygen saturation histogram data was available one day before and after the transition between NIPPV and CPAP. FiO2 at the time of data collection was greater than 21 percent. This histogram data, the percentage of time spent in certain SpO2 ranges, was compared before and after the de-escalation from NIPPV to CPAP or escalation from CPAP to NIPPV. FiO2 was additionally compared between the two modes of respiratory support.
Results: A total of 26 infants were included. The median gestational age was 25.5 weeks and the median weight of the infants was 792 grams. Among the 26 infants, there were 34 episodes of transition between NIPPV and CPAP, 19 switches from NIPPV to CPAP, and 15 from CPAP to NIPPV. The percentage of time that oxygen saturation was within the target range (89-94 %) was not statistically significant between the two modes of respiratory support (CPAP 39.9% vs. NIPPV 43.9%, p=0.09) (Table 1). The percentage of time that oxygen saturation was between 86-88% was higher on NIPPV and the percentage of time that oxygen saturation was \u3e94% was higher on CPAP. There was a trend towards lower FiO2 on NIPPV compared to CPAP. When switched from NIPPV to CPAP, there was a higher percentage of time spent above the target range ( \u3e94%) while on CPAP (56% vs 49%, p=0.001), and below the target range (86-88%) while on NIPPV (5.0% vs 1.4%, p=0.02) (Table 3). When switched from CPAP to NIPPV, there was no difference in oxygen saturation ranges (Table 2).
Conclusion: Target oxygen saturation ranges on histogram data were similar in premature infants when supported on CPAP and NIPPV. However, oxygen saturation below the target range was more frequent on NIPPV compared to CPAP. NIPPV is not superior to CPAP in maintaining oxygen saturation within the target range in premature infants on moderate non-invasive respiratory support. The potential risk of low oxygen saturation range while supported on NIPPV in preterm infants requires further research.https://jdc.jefferson.edu/pulmcritcareposters/1003/thumbnail.jp
Morphology of Influenza B/Lee/40 Determined by Cryo-Electron Microscopy
Cryo-electron microscopy projection image analysis and tomography is used to describe the overall architecture of influenza B/Lee/40. Algebraic reconstruction techniques with utilization of volume elements (blobs) are employed to reconstruct tomograms of this pleomorphic virus and distinguish viral surface spikes. The purpose of this research is to examine the architecture of influenza type B virions by cryo-electron tomography and projection image analysis. The aims are to explore the degree of ribonucleoprotein disorder in irregular shaped virions; and to quantify the number and distribution of glycoprotein surface spikes (hemagglutinin and neuraminidase) on influenza B. Projection image analysis of virion morphology shows that the majority (∼83%) of virions are spherical with an average diameter of 134±19 nm. The aspherical virions are larger (average diameter = 155±47 nm), exhibit disruption of the ribonucleoproteins, and show a partial loss of surface protein spikes. A count of glycoprotein spikes indicates that a typical 130 nm diameter type B virion contains ∼460 surface spikes. Configuration of the ribonucleoproteins and surface glycoprotein spikes are visualized in tomogram reconstructions and EM densities visualize extensions of the spikes into the matrix. The importance of the viral matrix in organization of virus structure through interaction with the ribonucleoproteins and the anchoring of the glycoprotein spikes to the matrix is demonstrated
Pennsylvania Folklife Vol. 18, No. 4
• Discord in the Garden • The Folk Festival Seminars: Crafts and Customs of the Year • What to Read on the Amish • Soup\u27s On! • Festival Highlights • Folk Festival Program • Folk Festival Geisinger • Four Interviews with Powwowers • The First Historian of the Pennsylvania Germans • The Public Sale Sixty Years Ago • The Long Shingle • Quilts and Quilting: Folk-Cultural Questionnaire No. 12https://digitalcommons.ursinus.edu/pafolklifemag/1036/thumbnail.jp
Odd skipped-related 1 controls the pro-regenerative response of fibro-adipogenic progenitors
Skeletal muscle regeneration requires the coordinated interplay of diverse tissue-resident- and infiltrating cells. Fibro-adipogenic progenitors (FAPs) are an interstitial cell population that provides a beneficial microenvironment for muscle stem cells (MuSCs) during muscle regeneration. Here we show that the transcription factor Osr1 is essential for FAPs to communicate with MuSCs and infiltrating macrophages, thus coordinating muscle regeneration. Conditional inactivation of Osr1 impaired muscle regeneration with reduced myofiber growth and formation of excessive fibrotic tissue with reduced stiffness. Osr1-deficient FAPs acquired a fibrogenic identity with altered matrix secretion and cytokine expression resulting in impaired MuSC viability, expansion and differentiation. Immune cell profiling suggested a novel role for Osr1-FAPs in macrophage polarization. In vitro analysis suggested that increased TGFβ signaling and altered matrix deposition by Osr1-deficient FAPs actively suppressed regenerative myogenesis. In conclusion, we show that Osr1 is central to FAP function orchestrating key regenerative events such as inflammation, matrix secretion and myogenesis
A central role for dityrosine crosslinking of Amyloid-β in Alzheimer’s disease
Background
Alzheimer’s disease (AD) is characterized by the deposition of insoluble amyloid plaques in the neuropil composed of highly stable, self-assembled Amyloid-beta (Aβ) fibrils. Copper has been implicated to play a role in Alzheimer’s disease. Dimers of Aβ have been isolated from AD brain and have been shown to be neurotoxic.
Results
We have investigated the formation of dityrosine cross-links in Aβ42 formed by covalent ortho-ortho coupling of two tyrosine residues under conditions of oxidative stress with elevated copper and shown that dityrosine can be formed in vitro in Aβ oligomers and fibrils and that these links further stabilize the fibrils. Dityrosine crosslinking was present in internalized Aβ in cell cultures treated with oligomeric Aβ42 using a specific antibody for dityrosine by immunogold labeling transmission electron microscopy. Results also revealed the prevalence of dityrosine crosslinks in amyloid plaques in brain tissue and in cerebrospinal fluid from AD patients.
Conclusions
Aβ dimers may be stabilized by dityrosine crosslinking. These results indicate that dityrosine cross-links may play an important role in the pathogenesis of Alzheimer’s disease and can be generated by reactive oxygen species catalyzed by Cu2+ ions. The observation of increased Aβ and dityrosine in CSF from AD patients suggests that this could be used as a potential biomarker of oxidative stress in AD
Managing Radiation Degradation of CCDs on the Chandra X-Ray Observatory--III
The CCDs on the Chandra X-ray Observatory are vulnerable to radiation damage from low-energy protons scattered off the telescope's mirrors onto the focal plane. Following unexpected damage incurred early in the mission, the Chandra team developed, implemented, and maintains a radiation-protection program. This program--involving scheduled radiation safing during radiation-belt passes, intervention based upon real-time space-weather conditions and radiation-environment modeling, and on-board radiation monitoring with autonomous radiation safing--has successfully managed the radiation damage to the CCDs. Since implementing the program, the charge-transfer inefficiency (CTI) has increased at an average annual rate of only 3.2x 10(exp -6) (2.3 percent) for the front-illuminated CCDs and 1.0x10(exp -6) (6.7 percent) for the back-illuminated CCDs. This paper describes the current status of the Chandra radiation-management program, emphasizing enhancements implemented since the previous papers
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